How can I remove the the union from this code? - sql

Question

I am attempting to remove the union in this sub-select due to performance issues. All attempts are unsuccessful because of how the AllocatedCRGReservedQty is calculated. How can I remove the union and combine the 2 select statements?
I was able to remove the union on the other portion of the query because it was based on a single where clause difference.
SELECT SrhCompanyID
,WhsPlantID
,SrhReason
,SrhRequestID
,SrdSeq
,SrdLotID
,SrdItemID
,InvQty
,SrdQty
,SrdSampleApprovedQty
,SrdUOM
,SohSalesOrder
,SohType
,AllocatedCRGReservedQty
FROM
( SELECT DISTINCT
SrhCompanyID
,WhsPlantID
,SrhReason
,SrhRequestID
,SrdSeq
,SrdLotID
,SrdItemID
,AsOfInventory InvQty
,SUM(SrdQty)
OVER (PARTITION BY SrdKey) SrdQty
,SUM(SrdSampleApprovedQty)
OVER (PARTITION BY SrdKey) SrdSampleApprovedQty
,SrdUOM
,SohSalesOrder
,SohType
,(SELECT SUM(SltLotAllocTranQty)
FROM SalesOrderLot
INNER JOIN
SalesOrderLotTran ON SltSolKey = SolKey
WHERE SolCompanyID = SodCompanyID AND
SolBranchID = SodBranchID AND
SolSalesOrder = SodSalesOrder AND
SolSalesOrderDtlKey = SodSalesOrderDtlKey AND
SolWipFgLotID = SrdLotID) AllocatedCRGReservedQty
FROM SampleRequestHdr
INNER JOIN SampleRequestDtl ON SrdSrhKey = SrhKey
INNER JOIN Warehouse ON WhsWhseID = SrhWhseID
INNER JOIN Lot ON LotCompanyID = SrhCompanyID AND
LotItemID = SrdItemID AND
LotID = SrdLotID
INNER JOIN #AsOfInventory ON IntLotKey = LotKey
-- Only include inventory transactions for completed production orders
-- Changed to temptable due to deadlocks on prodorder/prodorderreservation
INNER JOIN SalesOrderDtl ON SodCompanyID = SrhCompanyID AND
SodBranchID = SrdBranchID AND
SodSalesOrder = SrdSalesOrder AND
SodSalesOrderDtlKey = SrdSalesOrderDtlKey
INNER JOIN SalesOrderHdr ON SohCompanyID = SodCompanyID AND
SohBranchID = SodBranchID AND
SohSalesOrder = SodSalesOrder
WHERE SrhCompanyID = #CompanyID AND
((#PlantID <> '*' AND WhsPlantID = #PlantID) OR (#PlantID = '*')) AND
SrhApprovalExpireDate >= #As_Of_Date AND
ISNULL(SrdSampleRejected,'N') = 'N' AND
SohType IN ('Contract','Normal') AND
SrdQty <> 0
) WORK
WHERE ISNULL(AllocatedCRGReservedQty,0) < SrdQty -- if the lot is already allocated for at least the offered qty then don't include it so we don't over-state the gallons offered
UNION ALL -- then get the sample request qty offered for non-contract sales orders or no sales order assigned
SELECT SrhCompanyID
,WhsPlantID
,SrhReason
,SrhRequestID
,SrdSeq
,SrdLotID
,SrdItemID
,InvQty
,SrdQty
,SrdSampleApprovedQty
,SrdUOM
,SohSalesOrder
,SohType
,AllocatedCRGReservedQty
FROM
( SELECT DISTINCT
SrhCompanyID
,WhsPlantID
,SrhReason
,SrhRequestID
,SrdSeq
,SrdLotID
,SrdItemID
,AsOfInventory InvQty
,SUM(SrdQty)
OVER (PARTITION BY SrdKey) SrdQty
,SUM(SrdSampleApprovedQty)
OVER (PARTITION BY SrdKey) SrdSampleApprovedQty
,SrdUOM
,SohSalesOrder
,SohType
,(SELECT SUM(WptTranQty)
FROM WineProgram
CROSS APPLY
FN_CDV_WineProgramLotTranPlusPending(SrdLotID, WpgKey)
INNER JOIN
IntendedUse ON InuKey = WpgInuKey AND
InuIntendedUse = 'CRG'
LEFT JOIN
--ProdOrdDtl (NOLOCK) ON PodKey = wptPodKey
va_CDV_ProdOrder ON PodKey = wptPodKey
WHERE --WptLotID = SrdLotID AND
ISNULL(WptTranType,'') <> 'Pending' AND
((wptPodKey IS NOT NULL AND
(#CompletePOsOnly = 'N' OR -- include all POs
(#CompletePOsOnly = 'Y' AND PohCompleteDate IS NOT NULL))) -- Only include transactions if PO is Complete or if it's a non-PO transaction
OR
wptPodKey IS NULL
)
) AllocatedCRGReservedQty
FROM SampleRequestHdr
INNER JOIN SampleRequestDtl ON SrdSrhKey = SrhKey
INNER JOIN Warehouse ON WhsWhseID = SrhWhseID
INNER JOIN Lot ON LotCompanyID = SrhCompanyID AND
LotItemID = SrdItemID AND
LotID = SrdLotID
INNER JOIN
#AsOfInventory ON IntLotKey = LotKey
LEFT JOIN SalesOrderDtl ON SodCompanyID = SrhCompanyID AND
SodBranchID = SrdBranchID AND
SodSalesOrder = SrdSalesOrder AND
SodSalesOrderDtlKey = SrdSalesOrderDtlKey
LEFT JOIN SalesOrderHdr ON SohCompanyID = SodCompanyID AND
SohBranchID = SodBranchID AND
SohSalesOrder = SodSalesOrder
WHERE SrhCompanyID = #CompanyID AND
((#PlantID <> '*' AND WhsPlantID = #PlantID) OR (#PlantID = '*')) AND
SrhApprovalExpireDate >= #As_Of_Date AND
ISNULL(SrdSampleRejected,'N') = 'N' AND
ISNULL(SrdUseCRGReservation,'N') = 'N' AND -- if the SrdUseCRGReservation flag = "N" then return the sample qty
ISNULL(SohType,'') NOT IN ('Contract','Normal') AND -- offered to reduce the ATP (pseudo reservation until the sample expires or is approved/rejected)
SrdQty <> 0
) WORK